/Engine/Plugins/Runtime/MeshModelingToolset/Source/ModelingComponents/Public/Selection/PolygonSelectionMechanic.h
Initialize the Active Selection based on the provided Triangle-topology FGeometrySelection
void SetSelection_AsTriangleTopology ( const [UE::Geometry::FGeometrySelection](API\Plugins\DynamicMesh\Selections\FGeometrySelection) & Selection )